Liquid cooler, including agitator motor and heat removing device therefor



Mayl?, 1949. M. w. FlsH 2,470,551

LIQUID COOLER, INCLUDING GITTOR NOTQR AND HEAT REMOVING DEVICE THEREFOR Filed Sept. 13, 1946 BY Mok T/Mfe BSH,

Passed May 11, 1949 2,470,551

UNITED STATES PATENT QFFICE LIQUID CooLEa, INCLUDING AGITA'roa Moron AND HEAT aEMovrNG DEVICE A 'rnaaeroa Mortimer W. Fish, Dayton, Ohio, assigner to General Motors Corporation, Dayton, Ohio, a corporation of Delaware Application September 13, 1946, Serial No. 696,646

2 Claims. l

This invention relates to refrigeration and particularly to refrigerated beverage coolers.

In bottled beverage cooling and storing apparatus of the so-called wet type wherein the content of the bottles is cooled by submerging the bottles in a body of liquid contained in an in sulated compartment it is customary to cause agitation and circulation of the liquid over an evaporator or cooling element ci a reirigerating system in order to cool the liquid and more rapidly remove heat from the bottled beverages. An agitator or propeller is ordinarily employed for circulating the cooling liquid and may be con tinuously or intermittently operated by an elecu tric motor disposed above the body of liquid. It has been found that if heat generated by such an electric motor is not removed therefrom a loss in operating eiilciency occurs and also the covering or coating on the wire ileld windings of such a motor will become charred resulting in short circuits and failure oi' the motor. My invention is specifically directed to providing means whereby these difficulties will be eliminated.

An object of my invention is to provide an irnproved and substantially trouble-free refrigerating apparatus of the bottled beverage cooling, storing and dispensing type.

A further and more speciiic object of my invention is to provide means for rapidly removing heat from a motor employed to operate a liquid agitating and circulating element in a bottled beverage cooling and storing compartment of a reirigerating apparatus.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a perspective view of a bottled beverage cooling and storage apparatus having my invention embodied therein;

Fig. 2 is an enlarged fragmentary sectional view f the apparatus shown. in Fig. 1 and is taken on the line 2--2 thereof; and

Fig. 3 is a fragmentary view taken on the line 3-3 of Fig. 2, partly in section and partly in elevation.

Referring to the drawings, for illustrating the invention. 'I have shown in Fig. 1 thereof a refrigerating apparatus including a cabinet I0 having an access opening in its top wall which opening is normally closed by doors Il. This opening permits. when a door il is opened. articles stored in the cabinet to be dispensed therefrom. The

character 44 (see Fig. 3).

cabinet I0 comprises outer metal shells or panelsi2 and an inner metal open-top tank or liner if forming a compartment i5 within the cabinet (see Fig. 2). Any suitable or desirable insulating material it is interposed between the metal walls i2 and i4 of compartment i5 to insulate same. The cabinet outer shells or panels i2 extend downwardly beyond the bottom insulated wall of compartment i5 and forms a machine compartment i'i therebelow for housing the refrigerant compressing, liquefying and circulating unit (not shown) ci any suitable or conventional construction.

The closed reirigerating system associated with cabinet iii includes, in addition to the refrigerant compressing, liquefying and circulating unit, a refrigerant evaporator in the form of a cylindrical conduit coil 2i supported on a plurality o suitable brackets 22. The evaporator 2i also includes an accumulator tank 2li in which any liquid refrigerant flowing from the outlet of the evaporator is trapped and caused to be evaporated so as to prevent liquid refrigerant from entering the gaseous refrigerant return conduit 24 that is connected to the compressor `of the circulating unit. Liquid refrigerant is circulated, under the control of a suitable or conventional restrictor or expansion valve (not shown), to the refrigerant evaporating conduit'coil 2| through the pipe or conduit 26 leading from the condenser-receiver of the closed refrigerating system. The conduits 24 and 26 may be suitably sealed to the bottom wall of compartment l5 to prevent leakage at the point they pass through this Wall.

A propeller or agitator 28 is located below the evaporator coil 2i and is operatively connected to an electric motor 30, located above the evaporator 2i, by a shaft 3l. through a central tube-like part of the tank 23 and rotates in a bearing supported thereby. Motor 30 includes the usual cylindrical outer casing 36, a rotor 3l and a stator 38 surrounding the rotor and secured in contact with the inner wall surface of casing 36 (see Fig. 3) .y The motor 3B also includes the usual end caps 4i and 42 fitting into the ends of casing 36 and provided with bearings in which the shaft of the rotor 3l is rotatably mounted. The stator 38 of motorii comprises eld windings, generally represented by the reference character 43, and being in the form of suitably insulated wire wound around and into openings of a metallic pole forming member generally represented by the reference In order to support This shaft 3i passes motor 30 within compartment I5 above the evaporator 2| I provide a bracket device 46 which includes a pair of short legs 41 abutting and secured to the compartment liner I'4 by bolts 48. The bracket device 46 also includes outwardly extending relatively long legs 49 having screws I passing therethrough and threaded into the motor casing 36 to rigidly mount the motor in place. Bracket device 46 also includes a cross piece 52 extending between the legsv 49 thereof for supporting a metallic member 54 of high heat conductive property such, for example, as copper or brass. Member 54 is si :ured to the cross piece portion 52 of bracket device 46 by a bolt or the like 55. 'I'he member 54 comprises an arc-like band portion 51 and a plurality of spaced apart iin-like legs 58 depending therefrom and extending a substantial distance into a body of water placed in compartment I5 and used for a purpose to be presently described. 'I'he arc-like band portion 51 of member 54 is of slightly smaller radius than the diameter of the outer wall surface of the casing 36 of motor 30. Thus when member 54 is bolted in position the band portion 51 thereof springingly engages or embraces the outer wall surface of casing 36 of the motor 30 so as to be in intimate thermal contact therewith. This heat exchange relationship of member 5d with motor casing 36 and the extension of the spaced apart n-like leg portions 56 of ymember 54 into the body of water in compartment I5 provides an effective means for conducting heat away from motor 3u to a plurality of points or zones in the water.

A U-shaped, in cross-section, shroud 5i secured to liner lil in/any suitable manner such as by the bolts 48 forms a small chamber within compartment I5 and provides a shield for the motor ii and evaporator 2 i. This shroud is provided with a set of lower openings B2 and a set of upper open ings 63 for the ingress and egress of water circulated through the chamber and over the evaporator 2| by the propeller 26. Operation of propeller 2B draws water from compartment i5 through the openings 62 and causes the water to flow over the evaporator where it is cooled and then circulated out of the small chamber back into the compartment I5 and over the plurality of bottled beverages 64 located therein. As before stated.. operation of motor 30 to drive the propel ler 28 causes the eld windings d3 of the stator 38 to generate heat. This heat becomesexcessive and the motor attains .a temperature far above that desired for efficient operation thereof, and if the heat is not quickly and effectively removed from motor 30 it will cause the insulation on the wires of the field windings 43 to become charred or burnt, whereupon short circuits will occur. In the present disclosure I provide means for quickly removing heat from the motor casing 26, particularly from the field windings 43 of the motor, -so as to` permit the motor to operate at a temperature more desirable for efiicient operation thereof and to also prevent excessive heat from damaging the motor. This means is'the member 54 which enibraces a portion of motor 3lto conduct heat from the casing of the motor and consequently stator 38 to the body of cold water in compartment I5.

The partitioning of the small chamber from the compartment I5 by shroud 6I and operation of propeller 28 causes the level of water in the small chamber to rise above the level of the body of water in compartment I5 to thus submerge a Number greater amount of the lengths of the iin-like leg portions 58 of member 54 into the liquid which renders the member 54 more effective for removing heat from the motor 30. Due to the great temperature diiIerential between the heat ordinarily generated by a motor used for the purpose described -and the normal temperature of the body of cooling uid, the high heat conductive property of member 54 insures rapid transfer of the motor heat to the cold water. This effective heat transfer member is of low manufacturing cost and can be added to a refrigerating apparatus of the type disclosed for eliminating the difficulties hereinbefore enumerated without materially increas- Y ing the retail price of the apparatus.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. In a refrigerating apparatus including a cabinet having a plurality of walls forming an insulated compartment therein for the reception of articles to be cooled and stored; a body of liquid in said compartment, an evaporator of a refrigerating system for cooling said liquid, an agitator for circulating the liquid over said evaporator, an electric motor above the level of the vbody of liquid in said compartment and connected to said agitator for operating same, said motor including a casing, a rotor and a stator within said casing, said stator surrounding said rotor and engaging the inner wall surface of said motor casing, means for conducting heat directly from said motor casing to said body of liquid in said compartment, and said means comprising a metallic member having an arc=like band portion embracing a part of the outer wall surface of said motor casing within the horizontal plane of said stator and having integral spaced apart n-like leg portions depending into said body of liquid.

2. In a refrigerating apparatus including a cabinet having a plurality of walls forming an insulated compartment therein for the reception of articles to be cooled and stored, a body of liquid in said compartment, an evaporator of a refrign erating system for cooling said liquid, an agitator for circulating the liquid over said evaporator, an electric motor connected to said agitator for operating same, said motor including a casing surrounding a rotor and a stator, said casing having its outer wall surface exposed to ambient air within said compartment above the level of the body of liquid therein, said stator engaging the inner wall surface of said casing, and a metallic member having a part thereof embracing a portion of said outer wall surface of said casing Within the horizontal plane of saidlstator and having another integral part depending into said body of liquid for conducting heat generated by said motor directly from said casing to said liquid.

f MORTIli/IER W. FISH.

REFERENCES crren The following references are of record in the file of this patent:

Umm sra'rnsra'rmrrs Name Date Tanner Aug. 19, 1941 Chamberlain July 31, 1945 

